Programs available for viewing on television receivers today vary greatly in their content of such things as violence, nudity, depictions of sexual acts, strong language, or other things some people may regard as obscene or otherwise objectionable. Moreover, such television programs are available from a wide variety of sources including cable television systems, prerecorded video on tape or laser disk, as well as conventional broadcasts over the airwaves. Many parents would like to control the program content of what their children watch on television but find it nearly impossible to do so without being continually present. It would be desireable for parents to be able to control what programs their television set is able to receive in an unattended manner.
In accordance with the present invention, video signals transmitted to a television receiver have encoded in select portions thereof program codes which are indicative of the video signal's program content. The program codes may represent an arbitrary number of designations which rate the program content according to what degree it contains graphic sex, violence, and strong language, for example. The program code may be any type defining the requisite information and may be included at any available location of the video signal. A preferred way of implementing the program code, however, is for the video signal to carry such a digital program code in the so-called back porch region of the signal's blanking signal, which portion of the video signal is otherwise unused. Before reaching the picture generation elements of the television receiver, the video signal is received by control circuitry which extracts the program code from the composite video signal and compares it with a preselected reception code which represents the program content which is desired to either block or allow the reception of by the television receiver. The reception code may only be changed by use of a security device, such as a key-operated switch or lock, to allow such access. After electronically comparing the program code and the reception code, the video signal is either passed to the television display or is blocked. Blocking of select video signals may be accomplished by automatically operating or opening a switch or any equivalent method which disrupts the signal and prevents normal viewing. The control circuitry which receives the video signal may be provided integral with the televison receiver or separate therefrom and physically secured to prevent it from being bypassed.
It is therefore a primary object of the present invention to provide a system and method for controlling what video signals a television receiver is able to receive and display for viewing based on the program content of the video signals transmitted.
It is a further object to provide a system and method for effecting such control of video signals in an unattended manner.
It is a further object to provide a system and method for effecting such control of video signals in accordance with selecting respective of a plurality of different program content designations or codes.
Other objects, features, and advantages of the invention will become evident in light of the following detailed description considered in conjunction with the referenced drawings of a preferred exemplary embodiment according to the present invention.